Olsen died at a Los Angeles hospital, his alma mater, Utah State University, said in a statement on its website.

He was inducted into the Pro Football Hall of Fame in 1982, after a career with the Los Angeles Rams of the National Football League that spanned from 1962 to 1976.

During the 1960s, Olsen played defensive lineman with Deacon Jones, Rosey Grier and Lamar Lundy, who collectively became known as the “Fearsome Foursome” for their ability to stop ball-carriers and sack opposing quarterbacks.

Olsen missed only two games during his pro career, said Utah State, which called Olsen the best athlete in the school’s history.

“He was a great athlete and an even better man,” said Olsen’s former agent, Bob Williams of Burns Entertainment and Sports Marketing in Evanston, Illinois.

After football, Olsen turned to a career in acting and starred in the television drama “Little House on the Prairie” from 1977 to 1982, playing Jonathan Garvey, a friend of the main family in the series about 19th century rural America.

Olsen appeared in a number of other TV series during the 1980s, and he also returned to sports as a commentator for TV coverage of NFL games.